Switching mechanism



May 19, 1925.

O. F. FORSBERG' SWITCHING MECHANISM Filed Feb, 6. 1923 Patented May 19, 1925.

UNITED" STATES PATENT oFmc-s.

oscen r. Fons-nuns, oryouxnas, new YORK, ASSIGNOR TO wnsyrnnn nrncrmc con rams, mconronarsn, or NEW YQBK, N: A CORPORATION or New; YORK.

SWITCHING MECHANISM.

A lic tio -sue.Februar e, 192:}. SeriaLNn. 617 242.;

'To allgwkmw z'tmay concern:

Bait known that I, Os'oAn F. EORSBERG, a: citizen of the. United StatesofAmer-ica, msidingat Yonkers, in theco-unty of VVestchesterand State of New York, have invented certain new and. useful Improvements; in, Switching Mechanisms, 01:" which the following. isja full, clear, concise, and exact description This invention relates-to switching niechanisins. and more particularly to th socalled coordinate switch of: the type employed in automatic telephone exchanges.

In switches ofi the above mentioned character, operating, cards, are provided for sets of: active contacts and? by, the conjoint operation of. coordinately disposed bars, thecards are moved in such a manner as to carry the active contacts into engagement with setsofpassive or gridi conductors thereby; effecting telephonic connection-s between; calling and called subscribers lines associated with theswitch contact sets.

In such a switclt as is particularly disclosed in Britishl atent No. 183,438; issued to ester-n Electric Company, Limited; accepted September 6, 1923, it is desirablethat the verticab operatingbars. be sectionalized, there being one section for each group ofi sets. of" horizontal link or grid conductors and" all the sections being. rigidly coupled to for-m a, singleoperating unit capable of actuationby a single operating means. 110

function efficiently, switches o'f'this; nature must b quickoperatingand toobtain this desirable characteristic, the bearings pro vided for the rotatable members should be o'fsuchi a, nature as to reduce iriction to a minimumi It is not unlikely that; during the shipping of such switches, the. vertical operating members become bent or slightly bowed whichresults in considerable binding at the bearings of the vertical rods thereby increasing friction and reta1'7dinsthemovement of the vertical operating; rods.

It. is, therefore, an object of this invention to preclude: the possibility: of: inefiicient operation of the operating herein a; coordinate switch. caused by; the inaccurate align inentot the sections. thereof. i a

This object is. accomplished by providing the vertical operating rod sections with couplings having a, pin: ande-slot arrangement mningi a universal joint. By. the use- 0f the specific couplingdisclosed" herein, the vertical operating-bars, though comprisingrigid sections arepractica-lly flexible operat; ing units.

The above and other objects of this in vention will be readily. discernible from the following detailed description and by reference to the accompanying drawing inwhich Fig. 1 shows the specific couplingto becovered in this application; Fig. 2 shows an improved top section of the vertical operating bars and its associated operating inechanisn'r; 3 shows a fragmentary view of a coordinate switch. embodying the features of this invention; Fig. 4 shows a portion. of the switch structure disclosed in; Fig. 8- pointing out the relative) positions of the activ and passive contacts and their respective operating bars, the. horizontal operating har being in its operated: position;

Referring to Fig. 1, there is shown a bracing element 10 which forms av part of; the switch structure shown in Fig. A section 11 of a vertical operating bar is provided with a sleeve 12 rotatably mounted; thereon and fittinga circular aperture in. the member 10. The sleeve 12 acts as a bearing for the vertical section 11. Se; surely mountedou the end of: th section 11 by a rivet.- oi: bolt '13 is a coupling sleeve 9 provided with two diagonally disposed slots 13% and 15- which extend-in the direction of. the axis of the sleeve for short lengths on the upper-end of the sleeve. A cylindrical aperture 8 is centrally located in the lower endiof the sleeve 9, through which the. upper end; ol'thesection 11 extends. A cylindrical aperture 116" is centrally located in theiupper end; ofthe sleeve 9 and is of a larger diameter than the section 17 otthe.- vertica-l operating bar into which th end of" section 11 also extends. The section 17 is provided with; a; transverse cylindrical aperture. which, houses the; main. body portion of a; pin. member 18 which. is provided: with two. projec-v tionsfitt-ingthe slots 14k and; 1:5 and serving to loosely-key the section. 17. to the sleeve 9: The lower end: of thesection 17 has a convex beaningsurface and normally rests on the concave upper end of the section 1 1. A springer latch member 20 has one end thereof? secured to the leeve 9 while the other end-passes through. one. of the pro--- jections of the pin member 18 and serves to latch the section 1? to the section 11.

in the establishment of a telephonic connection will hereinafter be described in detail, the upper bar 17 is rotated and through the medium of the extending portions of the pin 18, this movement is imparted to the sleeve 9 which in turn, being rigidly mounted on the section 11. causes this section to move in a like manner. The flexibility of the coupling is effected by virtue of the combined effects of the slots and pin arrangement. the clearance between the section 17 and the sleeve 9 and the respective cnvex and concave bearing surfaces of the sec tions 17 and 11. It is apparent from Fig. 1 that section 17 is free to move angularly through a limited distance relative to section 11. It will be understood that in switches wherein the vertical operating bars consist of more than two sections, the upper end of the section 17 will be a duplicate of the upper end of the section 11 and in like manner, the lower end of section 11 will correspond to the lower end of section 17.

Referring now to Fig. 2, there is shown the uppermost section of a vertical operating bar and its associated operating mechanism.

This section comprises a tong or fork-shaped member 21 which cooperates with a coupling element 22 rigidly secured to the next succeeding section 1'7 of the vertical operating oar which is provided with a bearing 23 similar to the bearing 12 in Fig. 1. The coupling member 22 is provided with diagonal slots which cooperate with the extending portions of the tong or fork-shaped member 2-1 in effecting a universal coupling between the member 21 and the next succeeding section 17.

A contact mounting element 24, integral with the member 27, is provided for the contacts 26. The member 27 has securely mounted thereon a cup-shaped bushing 60. The circular wall of the bushing 60 acts as a housing for the upper end of the coil spring 32 and is provided with a slot 61 which admits the end of the spring, thereby effecting the tensioning of the spring when he electroniagnct 31 is energized and the section 21 rotated. The bushing 60 insures a central location for the spring 32 with respect to the section 21.

The member 21 is provided with a projection 29 which cooperates with an arm 30 rigidly secured to the armature of the electromagnet 31 which is securely mounted on the framework of the switch. The energization of the magnet 31 causes the rotation of its associated section 21 through the medium of the cooperating elements 29 and 30. The upper end of the section 21 is provided with a lateral projection which actuates the contacts 26 subsequent to the energization of the magnet 31. The restoring spring 32 is provided to return the operating bar to normal subsequent to the deenergization of magnet 31.

To remove a vertical operating member from a coordinate switch of this type, the mounting element 27 and its associated contacts 26 are removed from the switch framework; the element 40 is then removed from the section 21; the bar is then drawn vertically, the coupling members 9 and their associated bearings 12 passing through the apertures in the bracing members 10 until the coupling member 22 clears the top of the switch frame. The coupling 22 is then removed from the next succeeding section and the remaining sections are again drawn vertically until the next coupling member 9 clears the top of the switch. This member is then removed in an obvious manner and the same procedure is continued until all of the sections have been removed. Itwill be noted that the bracing members 10 are provided with slots 35 which permit the passage of the canuning fingers 36 therethrough during the removal of the vertical rod sections. Each vertical operating bar is provided with a step bearing 39, which comprises in general, a bolt and lock nut, the head of the bolt being provided with a projection which fits a cavity in the lower section of the operating bar. In this manner, the head of the bolt acts as a bearing for the bar and by manipulating the lock nut, the operating bar may be adjusted vertically.

The following description made with reference to Figs. 3 and 4 will give a clear understanding of the operation of a switch of this type.

Sets of grid or passive conductors 40, 41 and 42 are securely fastened at their ends to a fixed member (not shown) forming a part of the switch structure. A support 43 of insulating material also suitably secured to the frame of the switchis provided for each row of sets of flexible contact springs or active conductors 44, 45 and 46. The supports 43 may be of any suitable length and may carry any number of sets of contact springs depending on the switch capacity desired. The free ends of each set of contact springs 44, 45 and 46 extend through oblique apertures 47 in operating members or cards 48. In normal position, the card 48 holds the contact springs out of engagement with the passive conductors.

Coordinately disposed bars 49 and 50 are adapted to be rotated through small angles by the actuation of armatures 51 and 52, respectively, upon the energization of electromagnets 53 and 54, the armatures 51 and 52 being securely mounted on the operating bars 49 and 50, respectively. 7

The supporting member 43 also supports a flexible spring member 55, the free end of which extends through a circular aperture in its associated car 48. Each vertical operating bar 49 is provided with a plurality of camming elements 36 which cooperate with an extending finger member 56 rigidly mounted on a horizontal operating bar in effecting an engagement between a set of passive contacts 40, 41 and 42 and a set of active contacts 44, 45 and 46.

The operation of the switch is as follows: Assuming a subscriber desires to establish a connection, the removal of the receiver at the subscribers station will cause the energization of a vertical line magnet 53 individual thereto. Magnet 53, upon energizing, attracts its armature 51 causing the rotation 01 an associated operating bar 49. The rota tion of the bar 49 places the camming elements 36 in operable relation with their respective finger members 56. A horizontal link magnet 54 is then energized causing the rotation of a horizontal link bar 50. The rotation of the bar 50 causes the vertical movement oi the finger member 56, the free end of which slides along the cannning surface of the element 36 thereby causing the finger member 56 to engage the spring member in its upward movement. The s )ring member 55 is thereupon moved vertlcally and carries with it, its associated operating card 48 and a corresponding set of active contacts 44, 45 and 46 until the active contacts enga e a set of passive contacts 40, 41 and 42. y virtue of the oblique apertures 47 in the card 48, the active contacts are brought into engagement with the passive contacts with a wiping action. It is to be noted that the finger members 55 are provided with staggered projections forming a crotch which serves to hold the spring member 55 in engagement with the finger member 56 during the establishment of a connection.

It is apparent from the disclosure that the maintenance of a connection does not depend on the continued energization of magnets 53 and 54 but that the connection will be secured as long as the horizontal link magnet 54 remains energized irrespective of the energized condition of the vertical line magnet In this manner, a vertical line magnet such as 53 that has cooperated with a horizontal magnet such as 54 is establish ing a' connection may become deenergized and cooperate with another horizontal link magnet such as in the establishment of another connection. It will also be noted that the horizontal bar 50 in its operated condition holds the finger member 56 free' of the camming element 36 so that the member 56 is not disturbed upon the return of the vertical line bar 49 to normal.

The vertical and horizontal line bars such as 49 and 50 are returned to normal subsequent to the deenergization of their respective magnets by restoring springs such as 32.

lVhat is claimed is:

1. The combination in a switch structure having aplurality of sections, an operating member for each section, means for loosely joining said operating members to form a selfiadjustable single operating unit, and a plurality of members apertured for permitting the removal of the single operating unit in sections.

2. The combination in a switch structure divided into sections, an operating member for each of said sections comprising a pin and a slotted sleeve for forming universal joints with its adjacent operating members, and a single means for operating said operating members as aunit, the aforesaid joints adapted to permit the removal of said members individually.

3. The combination in a switch structure of coordinately disposed sets of contacts arranged in sections, means for operating said sets comprising intersecting bars, operating members on certain of said bars, one for each section, means for forming a loose coupling between said members to permit self-adjustment for slight deformities insaid members, said means comprising a sleeve which is fixedly mounted at one end of each of said operating members and which is provided at the other end with a boring of a diameter larger than that of the adjacent operating member, and means for operating said intersecting bars to effect an engagement between said contact sets, the intersecting bar which comprises several of said operating members being arranged to operate as a single unit.

4. In a switching structure, contact sets, a sectionalized operating member therefor comprising a plurality of flexibly coupled sections the uppermost section consisting of a tong-shaped member cooperating with a coupling normally associated with another section, and a lateral projection, and means cooperating with the lateral projection to cause the operation of said operating mem ber whereby engagement is effected between said contact sets.

In witness whereof, I hereunto subscribe my name this '2 day of February A. 1)., 1923 OSCAR F. F ORSBERG. 

